Mobile communication devices may include a variety of components including circuit boards, integrated circuit (IC) devices and/or System-on-Chip (SoC) devices. The components may include processing devices, user interface components, storage and other peripheral components that communicate through a shared data communication bus, which may include a serial bur or a parallel bus. General-purpose serial interfaces known in the industry, including the Inter-Integrated Circuit (I2C or I2C) serial bus and its derivatives and alternatives, including interfaces and protocols defined by the Mobile Industry Processor Interface (MIPI) Alliance, such as I3C, system power management interface (SPMI), and the Radio Frequency Front-End (RFFE) interfaces and protocols.
In one example, the I2C serial bus is a serial single-ended computer bus that was intended for use in connecting low-speed peripherals to a processor. Some interfaces provide multi-master buses in which two or more devices can serve as a bus master for different messages transmitted on the serial bus. In another example, the RFFE interface defines a communication interface for controlling various radio frequency (RF) front-end devices, including power amplifier (PA), low-noise amplifiers (LNAs), antenna tuners, filters, sensors, power management devices, switches, etc. These devices may be collocated in a single IC device or provided in multiple IC devices. In a mobile communications device, multiple antennas and radio transceivers may support multiple concurrent RF links.
In many instances, a number of command and control signals are employed to connect different components in mobile communication devices. These connections consume precious general-purpose input/output (GPIO) pins within the mobile communication devices and it would be desirable to replace the physical interconnects with signals carried in information transmitted over existing serial data links. However, serial data links may be associated with latencies that can prevent conversion of physical command and control signals to virtual signals, particularly in real-time embedded system applications supported by mobile communication devices that define firm transmission deadlines.
As mobile communication devices continue to include a greater level of functionality, improved serial communication techniques are needed to support low-latency transmissions between peripherals and application processors.